Roof truss forming machine

ABSTRACT

A ROOF TRUSS FORMING MACHINE FOR ASSEMBLING AND NAILING WITH NAIL PLATES TIMBERS INTO A PLANAR ROOF TRUSS INCLUDES A STATIONARY ELONGATED RAIL AND A PLURALITY OF BRIDGES EXTENDING LATERALLY THEREFROM AND ADJUSTABLY POSITIONED ALONG THE RAIL. EACH BRIDGE LONGITUDINALLY ADJUSTABLY CARRIES AT LEAST ONE BASE AND EACH BASE ROTATBLY ADJUSTABLY CARRIES A STAND WHICH SUPPORTS THE TIMBERS TO BE NAILED. EACH STAND MOVABLY CARRIES A CRADLE WHICH IS MOVABLE TOWARD AND AWAY FROM THE TIMBERS TO BE NAILED, AND EACH CRADLE SUPPORTS A HYDRAULICALLY OPERATED C-CLAMP FOR PRESSING THE NAIL PLATES INTO THE TIMBERS SUPPORTED BY THE STAND WHEN THE CRADLE IS MOVED TOWARD THE TIMBERS.

July 3, 1973 1:)- p POST Re. 27,692

ROOF TRUSS FORMING MACHINE Original Filed Feb. l0, i969 Sheets-SMM lJuly 3, 1973 D. Pv POST ROOF TRUSS FORMING MACHINE Originnl Filed Feb.1U, 1969 Sheets-Sham [haven-rca DONALD P. PosT Arrvs.

July 3, 1973 D. P POST ROOF TRUSS FORMNG MACHINE original Filed Feb. 1o,196e Sheets-Sheet Y Invsufoll DONALD P. PosT Sheets-Sheet 4 Inveuron.DONALD P. POST July 3, 1973 D, P POST ROOF TRUSS FORMTNG MACHINEoriginal Filed Feb. 1o, 1969 July 3, 1973 D. P, POST ROOF TRUSS FORMNGMACHINE 5 Sheets-Sheet :i

Original Filed Feb. 10, 1969 IIII 59 ffmmgv R om To ND. .hun D L m; N OD ALM A1' rvs,

United States Patent O 27,692 ROOF TRUSS FORMING MACHINE Donald P. Post,Palatine, Ill., assigner to Structomatic, Inc., Chicago, lll.

Original No. 3,530,790, dated Sept. 29, 1970, Ser. No. 798,031, Feb. 10,1969. Application for reissue Dec. 29, 1971, Ser. No. 213.758

Int. Cl. B301; 1/18 U.S. Cl. 100-100 14 Claims Matter enclosed in heavybrackets I appears in the original patent but forms no part of thisreissue specification; matter printed in italics indicates the additionsmade by reissue.

ABSTRACT OF THE DISCLOSURE A roof truss forming machine for assemblingand nailing with nail plates timbers into a planar roof truss includes astationary elongated rail and a plurality of bridges extending laterallytherefrom and adjustably positioned along the rail. Each bridgelongitudinally adjustably carries at least one base and each baserotatably adjustably carries a stand which supports the timbers to benailed. Each stand movably carries a cradle which is movable toward andaway from the timbers to be nailed, and each cradle supports ahydraulically operated C-clamp for pressing the nail plates into thetimbers supported by the stand when the cradle is moved toward thetimbers.

A principal object of this invention is to provide an improved rooftruss forming machine which is substantially completely adjustable sothat planar roof trusses of substantially any size and configuration maybe readily assembled from timbers and nailed with nail plates, such as,for example, king post, hip, shed, girder, monopitch, tink scissors,tlat, cambered or the like trusses, it even being possible to assembleand nail a circular truss if this should be desired, which isinexpensive to manufacture and assemble; which is simple in constructionand simple to assemble and adjust; which can assemble and nail trussesin a minimal time period with minimal manpower and expense; and whichcan simultaneously press nail plates into the opposite sides of thetimbers of the roof truss with simple hydraulically operated C-clampswhich are adjustably positioned to face the work and which can bereadily moved toward and away from the work to facilitate placement ofthe timbers and removed of the nailed truss.

Briey, the roof truss forming machine of this invention for assemblingtimbers and nailing them with nail plates into a planar roof trussincludes a stationary elon gated rail and a plurality of bridgesextending laterally therefrom and adjustably positioned along the rail.Each bridge longitudinally adjustably carries at least one base and eachbase rotatably adjustably carries a stand which supports the timbers tobe nailed. By this completely adjustable structure the stands may beadjustably positioned in any desired lateral positions and may beadjustably rotatably positioned to always face the timbers so thattrusses of substantially any size and configuration may be readily andaccurately assembled.

Each stand movably carries a cradle which is movable toward and awayfrom the timbers to be nailed and each cradle supports a hydraulicallyoperated C-clamp for pressing the nail plates into the timbers supportedby the stand when the cradle is moved toward the timbers. When thecradles and the C-clamps carried thereby are moved away from the timbersthe nailed truss may be readily removed from the stands and new timbersmay be readily assembled on the stands without interference from theC-clamps. This allows for assembling and nailing of trusses in a minimalof time with minimal manpower and Re. 27,692 Reissued July 3, 1973 ICCexpense. The hydraulically operated C-clamps and their mounting on thecradles are such as to provide for the simultaneous pressing of nailplates into both sides of the timbers in a simple and effective manner.

Other objects of this invention reside in the details of construction ofthe roof truss forming machine and the component parts thereof and inthe cooperative relationship between the component parts of the machine.

Further objects and advantages of this invention will become apparent tothose skilled in the art upon reference to the accompanyingspecification, claims and drawings in which:

FIG. 1 is a top plan view of the roof truss forming machine of thisinvention;

FIG. 2 is an enlarged side elevational view of a portion of the machinelooking from the right of FIG. l;

FIG. 3 is a top plan view of the lower portion of the machineillustrated in FIG. 2, the view being taken substantially along the line3 3 of FIG. 2;

FIG. 4 is a top plan view of the portion of the machine illustrated inFIG. 2;

FIG. 5 is an end elevational view of the portion of the machineillustrated in FIG. 2 and looking from the right of FIG. 2;

FIG. 6 is a sectional view through the upper portion of the machineillustrated in FIG. 2 and taken substantially along the line 6-6 of FIG.4;

FIG. 7 is a sectional view taken substantially along the line 7-7 ofFIG. 4 but showing the C-clamp closed;

FIG. 8 is a sectional View taken substantially along the line 3 8 ofFIG. 3;

FIG. 9 is a sectional view taken substantially along the line 9-9 ofFIG. 3;

FIG. 10 is a sectional view taken substantially along the line 10-10 o-fFIG. 3;

FIG. 11 is a diagrammatic sectional view taken substantially along theline 11--11 of FIG. 3; and

FIG. 12 is a top elevational view of the structure illustrated in FIG.l1.

Referring rst to FIGS. 1 and 2, the roof truss forming machine of thisinvention for assembling timbers and nailing them with nail plates intoa planar roof truss includes a substantially elongated rail generallydesignated at 10 and a plurality of bridges generally designated at 11extending laterally from the rail 10 and being adjustably positionedalong the rail 10. Any desired number of bridges 11 may be utilized,nine being illustrated by way of example. The bridges 11 may be of thesame length as illustrated in FIG. 1 0r the bridges may decrease inlength from the center bridge outwardly if this should be desired. Thebridges 11 are movably mounted at one end on the rail 10 so as to beadjustably positionable therealong and the other free end of the bridgesare provided with carriages generally designated at 12. These carriagessupport the free ends of the bridges 11. Each bridge 1l longitudinallyadjustably carries at least one base generally designated at 13 and eachbase 13 rotatably adjustably carries a stand generally designated at 14which supports the timbers to be nailed. Each stand movably carries acradle generally desigated at 15 which is movable toward and away fromthe timbers to be nailed and each cradle supports a hydraulicallyoperated C-clamp generally designated at 16 for pressing the nail platesinto the timbers supported by the stand 14 when the cradle 15 is movedtoward the timbers. The cradles 15 and C-clamps 16 are illustrated inthe advanced position in the drawings where they have been moved towardthe timbers to be nailed. The roof truss forming machine is supported bythe floor generally designated at 17, the stationary elongated rail 10being secured to the floor and the carriages 12 being rollable along andsupported by the floor when the bridge members l1 are moved along thestationary rail l0.

In FIG. l the stands 14 of the roof truss are shown t0 be positioned forfabricating a girder truss, the top and bottom timbers of the trussbeing shown in broken lines at 110. For clarity, the bracing members ofthe girder truss between the timbers 110 have not been illustrated.

As shown more clearly in FIGS. 2 and 3, the stationary elongated railincludes a round bar 20 which is welded to an inverted T-bar 21 which inturn is secured to pads 22 which are fastened to the oor 17. Care istaken in mounting the rail 10 to make sure that the rod 2t) is straightand level. The rod and T-bars 21 may extend the length of the machine orthey may be made in sections lengthwise of the machine and aligned bysuitable dowels etxending into the ends of the rod sections 20.

Each bridge 11 includes a pair of outwardly facing channels 24 which arewelded together by tubes 25 welded therebetween. A plate 26 is welded tothe channels 24 and this plate carries a pair of brackets 27 providedwith circular bores therethrough and a downwardly communicating slot.The brackets 27 carry split anti-friction bushings which arediagrammatically illustrated in more detail in FIGS. 11 and l2. Thesebushings include longitudinally extending and communicating grooveswhich contain a plurality of balls 29. The brackets 27 of the bridges 11are received over the rods 20 carried by the T-bar 21, the brackets 27having slots and the anti-friction bushing being being split toaccommodate the T-bar. As the brackets 27 and the birdges 11 carryingthe same are moved longitudinally along the rod 2l), the balls 29 rollon the rod 20 in the grooves in the bushings 28 so as to provideantifriction movement of the bridges 11 with respect to the stationaryrail 10. As a result, the bridges 11 may be moved along the rail 10 inan extremely easy fashion. The plate 26 of each bridge member carries apair of pressure screws 30 which are screw threadedly mounted in theplate 26. The screws 30 carry universally mounted pressure pads 31 whichare adapted to engage and disengage the T-bar of the rail, the screws 30being operated towards this end by knobs 32. Thus, as the bridge 11 ismoved to a desired poistion along the rail 10, the pressure screws 30may then be tightened to clamp the bridge 11 to the rail 10 at thedesired selected position.

The other free end of each bridge 11 has an angle iron 34 welded betweenthe channels 24 and the carriage generally designated at 12 is suitablysecured to this angle iron 34 as by bolts 36 or the like. As shown moreclearly in FIGS. 2, 3 and 5, the carriage generally designated at 12 ischannel shaped in contiguration including an angle iron 35 and a platewelded thereto. A pair of wheels 37 are rotatably mounted in the channelshaped carriage 12 by pins 38. The wheels 37 can engage the tloor 17 soas to rollingly support the outer free end of the bridge 11 as it isadjustably positioned along the rail 10. The channel has welded theretoa pair of plates 39 and a pair of plates 4I) are welded to the channelshaped carriage and the plates 39. A pair of pressure screws 41 arethreaded into the plates 40 and they are provided at their lower endswith pressure pads 42, the pressure screws 41 being rotated by knobs 43.When the bridge 11 is moved to its desired position, the pressure screws41 are operated to cause the pressure pads 42 to engage the lloor 17 andlift the carriage 12 and, hence, the wheels 37 from the floor 17. Inthis way, the carriage and the free end of the bridge 11 are secured inproper adjusted position.

As shown more clearly in FIGS. 2, 3, 5, 8 and 9, the base 13 includes apair of inwardly facing channels 45 which are welded to a plate 46 whichprovides an upwardly facing planar surface. A pair of angle irons 47 arealso welded to the plate 46 between the channels 45. As will be noted,the lower portions of the channels of the base 13 underlie the upperportions of the channels 24 of the bridge 11. Bearings 48 are secured tothe channels 45 of the base 13 and support a pair of shafts 49 which inturn carry rollers 50 which ride upon and are guided by the channels 24of the bridge 1 1. Thus, the carriage is longitudinally movable alongthe bridge 11 by means of the rollers 50. The upper surfaces of thelower portions of the channels 45 are provided with friction strips S1and the lower surfaces of the upper portions of the channels 24 areprovided with friction strips 52. Pressure screws 53 are threaded intothe plate 46 and channels 45 and they are provided at their lower endswith pressure pads 54, the pressure screws 53 being rotated by knobs 55.When the base 13 is moved to the desired adjusted position on the bridge11 as described above, the pressure screws 53 are then manipulated tocause the pads 54 carried thereby to engage the upper surface of thechannels 24 of the bridge. This moves the rollers 50 upwardly off of thechannels 24 and causes the friction strips 51 and 52 to engage forlocking the base 13 in desired position on the bridge 11.

The stand generally designated at 14 includes a circular plate 57 havinga lower planar surface which engages the upper planar surface of theplate 46 of the base 13. A pair of channels 58 are welded to thecircular plate 57 and also channels 59 are welded to the channels 58.Channels 60 which are welded to the channels 59 extend upwardly andcarry at their upper ends a plate 61 which is welded thereto and whichis adapted to support the timbers to be nailed by the nailing machine.Support plates 62 and 63 are welded to the channels 60 and the plate 61for reinforcing the latter. The plate 57 of the frame 14 and the plate46 of the base 13 are each provided with a central hole for receiving abolt 64 and nut 65 for rotatably mounting the plate 57 and, hence, thestand 14 on the plate 46 of the base 13, this rotatable mountingproviding for 360 rotation of the frame 14 with respect to the base 13.Provided around the circumference of the circular plate 57 are aplurality of clamp blocks 66 which are secured in place on the plate 46of the base 13 by screws 67. When the stand 14 is rotated to the desiredrotative position with respect to the base 13, the screws 67 aretightened to cause the blocks 66 to clamp the stand 14 in the properrotative position with respect to the base 13.

A pair of channels 7l] are secured to the channels 60 as by means ofbolts or the like. A plate 71 is welded between the forward ends of thechannels 70 and a strap 72 is suitably secured between the other ends ofthe channels 70 as by means of bolts or the like. Bracing members 73 arewelded to the channels 70 and are suitably secured, as by a plate andbolts to the channels 59' and 60 of the stand, the bracing members 73supporting the overhang of the channels 70. A pair of bars 75 are weldedto the upper surfaces of the channels 70 and a pair of rods 76 arewelded to the bars 75, the rods 76 forming a pair of rails extendingalong the channels 70.

The cradle generally designated at 15 includes a pair of angles 80 and aforward plate 81 and a rear plate 82 are welded to the angles 80 to forma rigid cradle construction. The angles 80 of the cradle carry two pairsof blocks 83 which in turn carry split anti-friction bushings 84 similarto the ones discussed above. These bushings 84 mount the cradle 15 onthe bars 76 so that the cradle 15 may be readily moved between retractedand advanced positions, the drawings illustrating the cradle 15 havingbeen moved toward the timbers to be nailed and, hence, in the advancedposition. Two pairs of sleeves 85 are welded to the channels 80, thesesleeves operating as vertical guide means for the hydraulically operatedC-clamp generally designated at 16.

The hydraulically operated C-clamp 16, as shown more clearly in FIGS. 4,5, 6 and 7, includes a platen 90 welded to a platen frame 91. The platenand platen frame 91 are secured to piston rod 93 carried by a pistonarranged within a hydraulic cylinder 94, the cylinder 94 being securedby bolts and nuts 96 to a plate 95. A pair of C- clamp members 98 arewelded to the plate 95 and they are secured together by a tube 99 andplates 101 welded thereto. The upper portion of the thus fabricatedC-clamp member has a pressure plate 100 welded thereto, the

pressure plate 100 being arranged above the platen 90. The supportingplate 61 which supports the timbers to be nailed is provided with anopening 103 for accommodating the platen 90 when it is moved upwardlyduring the nail plate pressing operation.

The platen 90 is provided with two pairs of depending pins 92 which areslidably mounted in the sleeves 8S of the cradle for guiding themovement of the C-clamp assembly. When the hydraulic motor including thecylinder 94 and the piston therein is operated to separate the platen 90from the pressure plate 100, the platen 90 rests against the angles 80of the cradle, this being caused by the weight of the C-clarnp assemblyand this position being illustrated in FIG. 5. In performing the nailingoperation, the cradle 15 and the hydraulically operated C-clamp areinitially in the retracted position and the timbers 110 are assembled onthe support plate 61 in proper position to be nailed. The support plate61 is preferably provided with jig means such as blocks or the like (notshown) removably secured thereto for guiding the timbers in properposition on the support plate. A nail plate 112 is placed on the platen90 and another nail plate 111 is placed upon the timbers 110 where thetimbers are to be nailed together. The cradle 15 and hydraulicallyoperated C-clamp are then advanced to a position Where the platen 90 isunderneath the timbers and the pressure plate 100 is above the timbers,this movement being permitted because of the wide space between theplaten 90 and the pressure plate 100. When the cradle 15 and the C-clamp16 are thus moved to the nailing position, the hydraulic motor includingthe cylinder 94 and the piston therein are operated to move the platen90 and the pressure plate 100 toward each other. At first the pressureplate 100 will usually first engage the nail plate 111 above the timbers110 and when resistance is met, the platen 90 is raised off of theangles 8l] to cause the nail plate 111 carried thereby to engage theundersides of the timbers 110. Thereafter, the platen 90 and thepressure plate 100 will substantially simultaneously move to presssimultaneously the nail plates 111 and 112 into the timbers 110 as isillustrated more particularly in FIG. 7. In this way, the nail platesare simultaneously driven into the timbers in a simple manner withoutthe need for extraneous linkages between the platen 90 and the pressureplate 100.

When the operation of the hydraulic motor is such as to separate theplaten 90 from the pressure plate 100, the platen 90 will tirst recedeand engage the angles 80 of the cradle and then the pressure plate 100will be moved upwardly to the position illustrated in FIG. 5. Eachcradle `15 and hydraulically operated C-clamp may then be retractedrearwardly to expose the nailed roof truss so that it may be readilyremoved from the stands 14 and new timbers readily assembled on thestands for forming another roof truss.

Hydraulic pipes 113 may extend along the iioor 17 adjacent thestationary rail 10, as shown in FIG. 2, and may be provided with Ts andtiexible hose connections to the cylinders 94 of the various C-clamps.By manipulating the hydraulic pressure from a suitable control point,all of the C-clamps 16 may be simultaneously opened and closed toprovide simultaneous nailing operations for the entire roof truss. Asillustrated in the drawings, the cradle 15 and C-clamps `1li may bereadily manually moved toward and away from the timbers supported by thestands 14, the forward motion being limited by the plate 81 of thecradle 15 engaging the plate 71 of the stand and being limited in itsrearward movement by the plate 82 of the cradle 15 engaging the strap 72of the stand 14. This movement may be manually performed or each standmay be provided with a hydraulic motor (not shown) to automatically andsimultaneously advance and retract all of the cradles 15 and theC-clamps 16 carried thereby.

While for purposes of illustration one form of this invention has beendisclosed, other forms thereof may become apparent to those skilled inthe art upon reference to this disclosure and, therefore, this inventionis to be limited only by the scope of the appended claims.

I claim:

1. A roof truss forming machine for assembling and nailing with nailplates timbers into a planar roof truss comprising, a stationaryelongated rail, a plurality of brides extending laterally from said railand movably supported at one end on said rail so as to be adjustablypositioned along said rail, a carriage at the free other end of eachbridge for movably supporting said free other end of the bridge, atleast one base movably supported on each bridge so as to be adjustablypositioned along the bridges extending laterally from said rail andmovably supported on each base so as to be rotatably adjustablypositioned with respect to the base, said stands having support meanssupporting the timbers to be nailed, a cradle movably supported on eachstand and movable toward and away from the timbers supported by thestand, and a hydraulically operated C-clamp supported by each cradle forpressing the nail plates into the timbers supported by the stands whenthe cradle is moved toward the timbers.

2. A roof truss forming machine as defined in claim 1 wherein saidstationary elongated rail comprises an elongated round rod secured to aninverted T-bar, and said one end of each of said bridges has a pair ofsplit antifriction bushings movable along said rod.

3. A roof truss forming machine as dened in claim 2 wherein said one endof each of said bridges is provided with at least one pressure screw forengaging the T-bar to secure the bridge in adjusted position along saidrail.

4. A roof truss forming machine as defined in claim 1 wherein thecarriage at the free other end of each bridge has a pair of wheels formovably supporting said other end of the bridge on the floor.

5. A roof truss forming machine as defined in claim 4 wherein saidcarriage is provided with a plurality of pressure screws for engagingthe floor to lift the wheels from the floor and secure the bridge inadjusted position.

6. A roof truss forming machine as defined in claim 1 wherein eachbridge has a pair of rails extending lengthwise thereof, and each basehas a plurality of rollers rollable on said rails for movably supportingthe base on the bridge.

7. A roof truss forming machine as defined in claim 6 wherein each basehas a pair of members underlying the pair of rails of the bridge, andeach base is provided with a plurality of pressure screws for engagingthe rails to lift the rollers from the rails and to clamp the pair of'members to the underside of the rail for securing the base in adjustedposition on the bridge.

8. A roof truss forming machine as defined in claim 1 wherein each basehas an upper planar surface, each stand has a lower circular flangedplanar surface supported on the upper planar surface of the base, and acentral pivotal connection is provided between the base and the standfor rotatably mounting the stand on the base.

9. A roof truss forming machine as defined in claim 8 wherein the basehas a plurality of hold down blocks engaging the flange of the circularplanar surface of the stand for securing the stand in angularly adjustedposition on the base.

l0. A roof truss forming machine as defined in claim 1 wherein eachstand has a pair of parallel rods, and each cradle has a plurality ofsplit anti-friction bushings movable along said rods to support thecradle on the stand for movement toward and away from the timberssupported by the stand.

ll. A roof truss forming machine as defined in claim 1 wherein eachhydraulically operated C-clamp includes a piston and a cylinder, aplaten secured to the piston and vertically movably guided by the cradleand normally resting by gravity on the cradle below the plane of thetimbers supported by the stand, and a C-clamp member secured to thecylinder below the platen and having a pressure plate above the plane ofthe timbers supported by the stand, the arrangement being such that whenthe cradle is moved toward the timbers supported by the support means ofthe stand with the platen and pressure plate of the hydraulicallyoperated C-clamp in vertical alignment with the timbers where they areto be nailed, the application of hydraulic pressure to the cylinder andpiston causes the platen to rise and the pressure plate t lower forsimultaneously pressing nail plates into opposite sides of the timbers.

[12. In a roof truss forming machine for assembling and nailing withnail plates timbers into a planar roof truss, the improvementcomprising, a stand having support means for supporting the timbers inposition where they are to be nailed, a cradle movably supported on thestand and laterally movable toward and away from the timbers supportedby the support means of the stand, and a hydraulically operated C-clampincluding a piston and a cylinder, a platen secured to the piston andvertically movably guided by the cradle and normally resting by gravityon the cradle below the plane of the timbers supported by the stand, anda C-clamp member secured to the cylinder below the platen and having apressure plate above the plane of the timbers supported by the stand,the arrangement being such that when the cradle is moved toward thetimbers supported by the support means of the stand with the platen andpressure plate of the hydraulically operated C-clarnp in verticalalignment with the timbers where they are to be nailed, the applicationof hydraulic pressure to the cylinder and piston causes the platen torise and the pressure plate to lower for simultaneously pressing nailplates into opposite sides of the timbers] 13. In a roof truss formingmachine for assembling and nailing with nail plates timbers into aplanar roof truss, the improvement comprising, a laterally adjustablypositionable base, a stand rotatably supported on the base so as to berotatably adjustably positioned with respect to the base throughsubstantially 360 angular degrees, said stand having support means forsupporting the timbers to be nailed, a cradle movably supported on thestand and movable toward and away from the timbers supported by thestand, and a hydraulically operated C-clamp supported by the cradle forpressing the nail plates into the timbers supported by the stand whenthe cradle is moved toward the timbers.

14. A roof truss forming machine as dened in claim 13 wherein saidhydraulically operated C-clamp includes a piston and a cylinder, aplaten secured to the piston and vertically guided by the cradle andnormally resting by gravity on the cradle below the plane of the timberssupported by the stand, and a C-clamp member secured to the cylinderbelow the platen and having a pressure plate above the plane of thetimbers supported by the stand, the arrangement being such that when thecradle is moved toward the timbers supported by the support means of thestand with the platen and pressure plate of the hydraulically operatedC-clamp in vertical alignment with the timbers where they are to benailed, the application of hydraulic pressure to the cylinder and pistoncauses the platen to rise and the pressure plate to lower forsimultaneously pressing nail plates into opposite sides of the timbers.

15. In a roof truss forming machine for assemblying and nailing timberson opposite sides with nail plates into a planar roof truss, theimprovement comprising, a stand having support means for supporting thellmbers in position where they are to be nailed, a cradle movablysupported on the stand and laterally movable toward and away from thetimbers supported by the support means of the stand, and a hydraulicallyoperated C-clamp including a piston and a cylinder, a platen secured lothe piston and vertically movable guided by the cradle and normallyresting by gravity on the Cradle below the plane of the timberssupported by the stand, and an unsuspended freely movable C-clamp membersecured to the cylinder below the platen and having a pressure plateabove the plane of the timbers supported by the stand, the arrangementbeing such that the entire weight of the hydraulically operated C-clampis supported by the cradle through the platen when the platen is restingby gravity on the cradle and being such that, when the cradle is movedtoward the timbers supported by the support means of the stand with theplaten and pressure plate of the hydraulic ally operated C-clomp invertical alignment will: the timbers where they are lo be nailed, theapplication of hydraulic pressure to the cylinder and piston causes thepressure plate to first lower and engage the nail plate above thetimbers so that the entire weight of the hydraulically operated C-clampis supported by the timbers and then the platen to rise and engage thenail plaie below the timbers with the timbers for thereaftersimultaneously pressing the nail plates into opposite sides of thetimbers.

References Cited The following references, cited by the Examiner, are ofrecord in the patented file of this patent or the original patent.

UNITED STATES PATENTS 3,100,301 8/1963 Black 227-152 X 3,207,406 9/1965Bowman 227-152 3.358,589 12/1967 Hentzschel 10D- 100 3,379,354 4/1968Moehlenpah et al. 227-152 3,388,657 6/1968 Jureit 1D0-208 BILLY J.WILHITE, Primary Examiner U.S. Cl. X.R.

